Python LXML-返回空列表 [英] Python lxml - returns null list

问题描述

当尝试从网页表中提取值时，我无法弄清楚XPATH出了什么问题.该方法似乎是正确的，因为我可以提取页面标题和其他属性，但是我不能提取第三个值，它总是返回一个空列表?

I cannot figure out what is wrong with the XPATH when trying to extract a value from a webpage table. The method seems correct as I can extract the page title and other attributes, but I cannot extract the third value, it always returns an empty list?

from lxml import html
import requests

test_url = 'SC312226'

page = ('https://www.opencompany.co.uk/company/'+test_url)

print 'Now searching URL: '+page

data = requests.get(page)
tree = html.fromstring(data.text)

print tree.xpath('//title/text()') # Get page title  
print tree.xpath('//a/@href') # Get href attribute of all links  
print tree.xpath('//*[@id="financial"]/table/tbody/tr/td[1]/table/tbody/tr[2]/td[1]/div[2]/text()')

除非我丢失了某些内容，否则XPATH似乎是正确的:

Unless i'm missing something, it would appear the XPATH is correct:

Chrome屏幕截图

我检查了Chrome控制台，看起来没问题！所以我很茫然

I checked Chrome console, appears ok! So i'm at a loss

$x ('//*[@id="financial"]/table/tbody/tr/td[1]/table/tbody/tr[2]/td[1]/div[2]/text()')
[
"£432,272"
]

推荐答案

您应指定元素名称.如果您不想指定特定的标签名称，则可以使用*:

You should specify element name. If you don't want specify specific tag name, you can use *:

print tree.xpath('//*[@id="financial"]/...')
                    ^

更新

在html文件中(只是在浏览器中呈现之前的html)，没有tbody标签.因此，您需要从表达式中删除tbody:

In the html file (just the html before the rendering in the browser), there's no tbody tag. So you need to remove tbody from the expression:

//*[@id="financial"]/table/tr/td[1]/table/tr[2]/td[1]/div[2]/text()

使用following-sibling轴的替代方式:

//div[text()="Total Assets"]/following-sibling::div/text()

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